1. Field of the Invention
This invention relates generally to mechanical tools and in particular to a dynamic vehicle tire and wheel balancing system.
2. Description of the Prior Art
Accurate balancing of any rotating body requires that it be free from the effects of external forces such as may be produced by its own rotating drive mechanism. Thus, if a tire and wheel is properly mounted on a rotatable axle or shaft of a wheel balancing machine, accurate measurements of imbalance can only be taken if the wheel and tire is not subjected to external disturbances, such as externally generated vibrations, if the axle itself is properly balanced in smooth accurate bearings, and if the rotational driving means cannot impart any vibration or other disturbances to the rotating shaft.
The disturbances generated by the rotating driving means is the most difficult to overcome and many different schemes have been attempted including the use of air-driven turbine drives, gear connected drives, belt drives, and the use of high precision electric motors connected either directly to one end of the shaft or through carefully aligned universal connectors. Motors for this application are therefore quite costly and, even though initially highly accurate, may easily be thrown out of proper alignment by careless handling to therefore impart a vibration to the drive shaft.
The balancing machine to be described eliminates the possibility of imparting externally generated disturbances to the rotating shaft and provides a highly accurate and convenient means for detecting wheel imbalance.